Railway-traffic-controlling apparatus



Jan. 17, 1928.

, L. O. GRONDAHL ET AL RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Feb. 4, 1925 2 Sheets-Sheep 1 ATTORNEY Jan. 17, 1928.

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uurrnn LABS 0. GRONDAHL, F PITTSBURGH, AND LEWIS I. NETTLETGN, OF "WILKINSBUEG, PENNSYLVANIA, ASSIGNORS TO THE UNION SWITCH dc SIGNAL GOMIANY, 0F SWISSVALE, PENNSYLVANIA, A CORPORATION 015' PENNSYLVANIA.

RAILWAY-TRAFFIC-CONTROLLING APPARATU$ Application filed February Our invention relates to railway traiiic controlling apparatus, and particularly to apparatus of the type comprising train carried governing means controlled by energy received from thetrackway.

We will describe two forms of apparatus embodying our invention, and will then point out the novel features thereof 1n claims.

In the accompanying drawings, Fig. 1 is a View, largely diagrammatic, showing one form of railway traffic controlling apparatus embodying our invention. Fig. 2 is a view showing a modified form of a portion of the train carried apparatus illustrated in Fig.

1, and also embodying our invention.

Similar reference characters refer to similar parts in both views.

Referring first to Fig. 1, the reference characters 1 and 1 designzite the track rails of a stretch of railway track over which trafiic normally moves in the direction indicated by the arrow. These rails are divided, by means of insulated joints 2, into a 2 plurality of track sect-ions, only one of which sections, AD, is shown complete in the drawing. The track section A-D is provided with trackway apparatus for transmitting current to trains in the form otcode impulse combinations, which apparatus is here designated in general by the reference character. Q. The impulse transmitting apparatus comprises a source of energy here shown as an alternator F, constantly connected with a motor E. The motor E is operatively connected with three circuit interrupting devices G, J and K all of which rotate at the same speed. Each of the interrupting devices G, J and K comprises a hat disk of insulating material provided at its edge with contact plates 6. It will be seen from the drawing that disk G has one pair of oppositely disposed plates 6, that disk J has two pairs of similar contact plates, and that disk K is provided with three sets of similar contact plates 6, the contact plates being circumferentially spaced about the edge of the disk, and that all the plates on each disk are connected together electrically. Each disk is provided with two oppositely disposed brushes 6 adapted to be connected together when a pair of contact plates engages the two associated till interval.

4, 19.25. semi 1%. 6,?18.

brushes. A circuit controller 3 is controlled by traiiic conditions in advance. When this circuit controller is open no current is supplied to the rails; when contact 3-4 is closed an impulse is delivered to the rails for each half-revolution of device Q, so that the trackway is then supplied with code impulse combinations of one impulse each; when contact 3- is closed the code impulse combinations supplied to the track rails each comprise two impulses separated by a time When contact 34 is closed the code impulse combinations in the trackway each comprise three spaced impulses. As here shown, the source F is an alternator, and it is, of course, apparent that each impulse impressed across the rails is in reality made up of a series of alternating current impulses or cycles, but for purposes of this specification we will refer to each of these series as an impulse. It should be understood that alternating current for the code combinations is not essential to our invention.

The code impulse combinations thus supplied to the track, control train carried governing means through the medium of receiving apparatus located on a train which is shown diagrammatically at O. This receiving apparatus comprises two magnetizable cores 54 and 54* located in advance of the forward axle 56 of the train and in inductive relation wth the two track rails 1 and 1, respectively. The cores 54 and 54 are provided with windings 55 and 55, respective ly, so connected that the voltages induced therein by varying currents flowing in the opposite direction in the track rails at an instant are additive. The total voltage thus created in the receiving windings 55 and 55 is applied to the terminals of a relay N so that the relay is energized by each impulse supplied to the trackway by apparatus Q. An amplifier may be interposed between relay N and the receiving windings 55 and 55. The relay N controls a selector designated in general by the reference character P. This selector comprises a contact device 17 in the form of a disk of insulating material, pivotally supported at its center 18 and provided at its periphery with two sets of teeth 21 and 22. A spring 19 constantly urges the disk 17 in a counterclockwise direction and the disk is therefore biased to the position in which it is illustrated, further motion in a counter-clockwise direction being prevented by a stop 20 which is engaged by one of the teeth 22. Rotation of the device 17 is controlled by an armature 13 pivoted at point 14. This armature is operated by a magnet 7 and is provided with a driving pawl 15 adapted to engage teeth 21. Disk 17 is further controlled by an armature 23 pivoted at point 24 and operated by a magnet 8. This armature is provided with a resilient arm 23 carrying a latching pawl 23 adapted to engage teeth 22. Magnets7 and 8 are both normally de-encrgized, but are both energized when relay N becomes energized, that is, when an impulse is transmitted to the trackway by device Q. lVhen magnet 7 is de-energized the armature 13 moves, under the influence of gravity, to the position shownin the drawing, in which position the pawl 15 is swung out of the path of the teeth 21. When magnet 7 becomes energized, the armature 13 is moved in a clockwise direction and the pawl 15 engages one of the teeth 21 and moves the disk 17 in clockwise direction, against the bias exerted by spring 19, by an amount equal to the pitch of one tooth 21.

When magnet 8 is de-energized armature 23 occupies the illustrated position. \Vhen magnet 8 becomes energized, this armature is swung in a counter-clockwise direction so that the pawl 23 engages one of the teeth 22 on disk 17, and if the disk has been moved away from its inital position by pawl 15 this engagement will prevent the disk from reall turning to such position. A bridging contact 25-2627 of the usual form is operated by armature 23 and is arranged to be closed-when the armature occupies an intermediate position, but to be open when the armature occupies either extreme position. The magnet 8 is so proportioned and constructed that a time interval elapses after the magnet is de-encregized and before the armature 23 is released, which interval is longer than the time interval between successive impulses in a code impulse combination, but less than the time interval between successive combinations, in the current supplied to the trackway by the transmitting apparatus Q.

This disk 17 carries at its edge three contact members 31, 32 and 33 electrically insulated from each other and adapted to cooperate with a fixed contact finger 34. The parts are so proportioned and disposed that as disk 17 is rotated in a counter-clockwise direction contact 3431, 3432, or 34-38 is closed according as the disk is rotated by a code combination of one, two or three impulses.

Four slow releasing relays 9, 10, 11 and 12 are controlled by the contacts on disk 17.

These relays each have a time element greater than the time interval between successive code impulse combinations supplied by device Q.

Traffic governing apparatus, here illus trated as four signal lamps S, H, M and L, is controlled by the relays 9, 10, 11 and 12. The circuit for relay 12 may be traced from one terminal B of a suitable source of energy, not shown in the drawing, through wires 28 and 29, winding of relay 12, wire 30, contact 3l34 of device 1, wire 35, contact 25-26--27 operated by armature 23, wire 36, winding of relay 9, and wire 37 to terminal C of the same source. lVhen this circuit is closed relays 12 and 9 both become energized and current flows from terminal B, through wires 41 and 42, front contact 43 of relay 12, wire 44, lamp L, wire 45, front contact 46 of relay 9, to terminal C, and lamp L is lighted.

Another circuit may be traced from terminal B, through wires 28 and 38, winding of relay 11, wire 39, contact 3234 of device P, wire 35, contact 252627 operated by armature 23, Wire 36, winding of relay 9, and wire 37 to terminal C. When this circuit is closed relays 9 and 11 are energized. Current then flows from terminal B, through wires 41 and 47, front contact 48 of relay 11, wire 49, lamp M, wires and 45, front contact 46 of relay 9, to terminal C, thus lighting lamp M.

A third relay circuit may be traced from terminal B, through wire 28, winding of relay 10, wire 40, contact 33-34 of device 1, wire 35, contact 25-26-27 operated by armature 23, wire 36, winding of relay 9, and wire 37 back to terminal 0. lVhen this circuit is closed relays 9 and 10 both become energized and current flows from terminal B, through wire 41, front contact 50 of relay 10, wire 51, lamp H, wires 45 and 45, front contact 46 of relay 9, to terminal C, thus lighting lamp H. It will be observed that the circuit for each of the relays 10, 11 and 12 also includes relay 9, and that consequently, whenany one of relays 10, 11 or 12 is energized, relay 9 will also be energized. \Vhen relay 9 is de-energized, however, current flows from terminal B, through 'wire 53, lamp 5, wire 52, back contact ll;

of relay 9, to terminal C, thereby lighting, lamp 5.

As shown inthe drawing circuit controller 3 is open and therefore no voltage is being supplied to the rails of section A-D. Relay N on board the train is therefore continuously de-energized. Magnets 7 and 8 are both de-ener ized, and armatures 13 and 23 occupy the, i1 ustrated position. Disk 17 is therefore held in its initial position and contacts 31-34, 3234 and 33-34 are all open. Relays 9, 10, 11 and 12 are all deenergized. As a result lamp-s L, M and H ltlll llll are all extinguished, but lamp S is lighted to indicate stop.

We will now assume that contact 3% of device Q becomes closed. The section A.D is then supplied with a single impulse code combination. Each such impulse energizes relay N which relay is, of course, doenergized during the time interval between impulses. lhe first closing of the front contact 80 of relay N completes the circuits for magnets 'l' and 8. Magnet '4' actuatcs armature 13 carrying the driving pawl 15 and rotates disk 1'? in a clockwise direction against the bias exerted by spring 19. The amount of this motion is such that contact 31-3l is closed. When relay N next be comes de energized, magnet 7 is deenergiaed, and armature 13 returns to the position illustrated in the drawing. The disk 17 does not return, however, to its initial position because pawl 23 latches the disk against movement. This latching ellect continues, due to the slow acting characteristics of magnet 8, for a fixed time interval after magnet 8 becomes (ls-energized due to the opening of N. But this time interval is, as has been explained, less than the time interval between successive impulses of the single impulse code combinations. At the expiration the time interval of magnet 8, then, the armature 23 releases, and in returning to its original position contact 26 27 is momentarily closed. Contact 31-23% is already closed, and relays 12 and 9 are therelore ener ized, thereby extinguishing lamp El and lighting lamp L to indicate proceed at low speed. lVhen the armature 23 is fully released contact 2526-27 opens and disk 17 returns to its initial position, breaking contact 31-34., but relays 12 and 9, beingslow releasing. hold their front contacts closed and lamp L continues to be lighted. 'lhe next impulse supplied to the trackway by device Q; causes relay N to again be encrgiaed, and the cycle of operations just doacribed is repeated. The time interval belCWQQll successive energizations of relays 1.2 and 9 is less thanthe release periods of these relays and therefore lamp L is continuously lighted. i

We will next assume that contact 3 l-' of device Q, is closed. Code impulse combinations of two impulses each are then supplied to the trackway. The first impulse in each such combination energizes relay N and actastes the apparatus as described before to close contact 31-34. During the compar' tively short time interval after the termination of such first impulse and prior to the commencement er the second impulse in the same combination, pawl 15 releases, but pawl does not release. The second energizaof role hl vvill actuate pawl 15, as

but since disk It? has not returned toits initial positiom'the disk is moved lurther in a clockwise direction so that contact 3234 is closed. When relay N is next .de-energized pawl 15 releases immediately but pawl 23* holds for a time interval. During the return of armature 23 to its normal position contact 25262'. is closed. The circuit is therefore completed for relays t) and 11, which relays become energized. Vthen pawl 23 has fully. released disk 17 returns to its initial position. The next group of impulses repeats the same opera tion and relays 11 and 9 are again supplied with a surge of current. Since these relays are sufiiciently slow acting to bridge the time interval between successive code impulse combinations, lamp M is continuously lighted to indicate proceed at medium speed.

Similarly, it contact 3% of device (,2 is closed the trackway is supplied with code impulse combinations, each such combination comprising three impulses. T he operation of the apparatus when such combinations are supplied to the trackivay Wlll be readily understood from the foregoing, it being sullicienthere to say that for each code impulse combination, disk 17 is swung into a position in which contact 333et is closed. The release of armature 23 after each combination then completes the circuit for relays 9 and 10, and these relays, being slow releasing, are continuously closed, and lamp H is lighted to indicate proceed at high speed.

Finally, we will assume that uninterrupted alternating current is supplied to the trackvvay as by the sticking of device Q; or because of some other abnormal condition. llelay N is therefore continuously energized. Magnets 'l' and 5) then become continuously energized. It will be seen that the operation oi armature 13 by magnet 7 will advance disk 17 one tooth so that contact Ell-34 is closed. Magnet 8 being energized, however, contact 25 26-27 operated there by is open, and relays 12 and 9 are both deenergized. Relays 11 and 10 are also, of course, tie-energized and a stop indication is therefore displayed by the lighting of lamp S. ta similar manner a stop indication would be displayed should relay Nbe continuously energized with disk 17 in such p0 sition as to close either contact 32-3l or 33-3-t The modilied form of train carried ap paratus illustrated in Fig. 2, is suitable for cooperation with the trackway apparatus shown in Fig. 1. That is to say, relay N is energized by code impulse combinations of '1 one, tvvo or three impulses in accordance with tin-the conditions. Device l? replaced by a device P comprising a dish 1'? pivotally supported at point 18 and provided on its periphery with. two spaced ot teeth 21 and 22. A radially extending arm 65, the luncran ltd

tions of which will appear hereinafter, is rigidly fastened to disk 17. The disk is biased to an initial position, in which position it is illustrated in the drawing, by means of a spring 19 which constantly urges the disk in a clockwise direction. Further motion of the disk in such direction is prevented by a lixed stop (36 which engages arm 65.

The motion of disk 17 is controlled by a driving magnet 58, and by a latching magnet 57 which controls an escapement yoke T adapted to cooperate with the teeth 21 and These magnets 58 and 57 are both supplied with energy over a front contact 80 of relay N and so are energized when relay N is energized. A plunger 59 of magnetizable material is resiliently connected with arm by means of a coil spring 67. When magnet 58 is energized plunger 59 is drawn downward, thus urging disk 17 in a counter-clockwise direction against the bias exerted by spring 19. By means of a cylinder 60 of conducting material surrounding plunger 59, magnet 58 is made slow releasing so that after this magnet is de-energized the driving torque exerted upon disk 17 through spring (i7 continues for a time interval greater than the interval between successive impulses in the same code impulse combination, but less than the time interval between successive combinations.

The escapement yoke T comprises a. pair of oppositely disposed detents 62 and 63, disposed on opposite sides of the disk 17 and arranged to cooperate with teeth 22 and 21, respectively. The whole yoke is pivotally supported at point- 61 and is provided with an armature 78 controlled by magnet 57. As shown in the drawing magnet 57 is de-encrgized and armature 78 has dropped down onto a fixed stop 79 under the influence of gravity. In this position of the yoke T, detent G2 is out of the path of teeth It will be observed that the detent ()3 is provided with a flexible finger 6-1 to prevent motion of the disk in a counterclockwise direction, but to allow motion of such disk in the opposite direction, when the yoke is in the position illustrated in the drawing.

The reference character R designates a contact mechanism controlled by the arm ()5 on disk 17. member pivoted at point 76 and biased by gravity to the position shown in the drawing. in which position the member rests upon a tixed stop '77. The member 7 5 is provided with three spaced insulated rigid contact fingers 69, 71 and 73, adapted to cooperate respectively with three flexible contact fingers 7 0, 7 2 and 74 which are electrically connected with the member 7 5, and therefore with each other. The end of arm 65 is provided with a flexible tongue 68 which engages the fingers 70, 72 and 74 as disk 17 moves in a This mechanism comprises a counter-cloelnvise direct-ion. The parts are so arranged that when arm 65 is swung downward the flexure of the tongue 68 and the contact fingers engaged thereby permit motion of the arm without disturbing the position of the member 75, but when the arm (35 returns to its upper position member 7 5 is rotated upwardly about its pivot, as will appear more in detail hereinafter.

The signal lamps S, L, M and H are controlled by relays 9, 10, 11 and 12 in the same manner as already described in connection with Fig. 1.

As shown in the drawing, the parts are in the positions corresponding to the continuously tie-energized condition of relay N. Under this condition magnets 57 and 58 are both tie-energized. Armature 78 engages stop 79 so that detent 62 is disengaged from teeth 22, and disk 17 occupies its initial porill sition under the influence of sprin 19. In 7 this position tongue 68 is above nger 70. All contacts of the contact mechanism R are open, and relays 9, 10, 11 and 12 are all de energized. Lamp S is therefore energized to indicate stop.

'0 will now assume that relay )1 is supplied with code impulse combinations of one impulse each. When the relay N becomes energized the closing of its front contact 80 completes the circuits for magnets 57 and 58 which magnets thereupon become energized. The energization of magnet 58 draws plunger 59 downward and exerts upon disk 17, through spring (57, a torque which urges the disk in a counterclockwise direction against the bias of spring 19. At the same time the energization of magnet 57 raises armature 78 and rotates the yoke connter-cloclnvise about pivot 61. During this motion the first tooth 21 is released, and disk 17 moves counter-clockwise the distance of one tooth, further motion in this direction being prevented by engagement of" a tooth 22 with detent 62. During this motion of disk 17, tongue 68 moves downwardly past finger 70. the resistance of the tongue and the anger permitting this motion, and tongue 68 now extends between lingers 70 and 72. At the end of the lirst impulse relay N becomes de-cncrgized. thereby (lo-energizing magnets 57 and 5S. Magnet 57 immediately releases. allowing yoke T to return to its original position. but due to its slow acting clniractcristics plunger 59 is held down for a time interval. During this interval disk 17 is held in place. the linger (it of detent (S3 engaging a tooth 21 and preventing further motion in a counterclockwise direction. The time interval during which plunger 59 is held down is, however, less than the time interval between successive code impulse combinations, and when plunger 59 is released by magnet 58, disk 17 returns to its initial position, the

Ill]

fiexure of finger 64 permitting the teeth 21' to pass in this direction. In returning to its initial position, tongue 68 engages finger and due to the resistance offered by the tongue to downwaiwl fiexure, finger 70 is bent upward to close contact 69-70. A circuit is then closed from terminal 13, through wires .28 and 29, winding of relay 12, wire 30, contact 69-70. member, 75, wire 36, winding of relay 9, and wire 37 back to terminal C. llelays 9 and 12 are therefore energized, lamp S is extinguished and lamp L is lighted. As the motion of disk 17 toward its initial position continues member T5 is swung upwardnntil finger 70 is released by tongue 68, and the member then drops back to its original position thereby opening contact 6970. The motion of disk 17 is arrested by stop 66 engagingarm 65. l i'hcn relay N receives the next impulse the same cycle ofopcrations is performed. It follows that when relay N is receiving code impulse combinations of one impulse each, relays l2 and 9 receive a surge of energy for each such combination. But. due to the slow releasing characteristics of theserclays, they hold their front contacts closed during the intervals between successive code impulse rombinations and lamp L is constantly lighted.

l-Ve will next assume that relay N is receiving code impulse combinations of two impulses each. During the first impulse of each combination disk 17 is rotated in a counter-clockwise direction for a distance of one tooth as explained in connection with the single impulse combinations thus bringin g tongue 68 between fingers 70 and 7 At the end of such first impulse the de-energization of magnet 57 allows yoke T to return to its original position to prevent the return of disk l7 as before, but before plunger 59 is released by magnet 58, relay N is energized by a second impulse. Magnets 57 and 58 therefore again become energized, the yoke 'l is again swung in a counter-clockwise direclion and disk 17 is moved, by torque applied through spring 67, into a position wherein tongue 68 is between fingers 7 2 and 7 At the end of this second impulse, the opening of relay N (ls-energizes magnets 57 and 58, and yoke 'l returns to its original position. Disk 17 is now held by finger 64 against further motion by the torque exerted by plunger 59. At the expiration of the time interval required for the release of magnet 58, spring 19 moves disk 17 back to its initial position. During this motion tongue 68 engages finger 72 and closes contact 7 1-7 2. A circuit is then closed from terminal B, through wires 28 and 38, winding of relay 11, Wire 39, contact Ti -72, member 75, wire 36, winding of relay 9, and wire 37 back to terminal C. Relays 11 and 9 then become energized and lamp M is lighted. As the motion of disk 17 toward. its initial position continues, member 75 is swung upwardly about its pivot until the tongue 68 moves out of the path of finger 72, whereupon contact Tl-i2 opens and member 75 drops hack into the position in which it is illustrated in the drawin The parts are so arranged that in thus returning to its original position, finger 70 does not engage tongue 68, and hence contact 69-40 does not become closed. The next group of impulses causes contact 7172 to again become closed, and relays 11 and 9 are therefore energized once for each code impulse combination. Relays 11 and 9 being slow releasing, lamp M is continuously lighted as long as relay l\' receives the two impulse code con'ibinations.

it will be plain from the foregoing that when relay N receives code'impulse combinations of three impulses each, the operation ot the apparatus will be similar to the operation Just described in connection with the two impulse combinations with the exception that with the three impulse code combinations, disk 17 will be advanced 3 teeth during each combination and that:

when the disk returns to its initial position, contact 73-7 l will be closed instead or contact Fl-72. The closing of contact 73-74 completes a circuit from terminal B, through wire 28, winding of relay 10, wire 40, contact 73-74, member 7 5, wire 36, winding of relay 9, and Wire 37 back to terminal (1. It follows that relays 10 and 9 are energized once during each code impulse combination. Due to the slow releasing characteristics of these relays their front contacts will remain closed during the period between successive energizations, and lamp H will therefore remain lighted.

Should relay N be continuously energized, as by the presence of uninterrupted alternating current in the trackway, magnets 57 and 58 both woulch be continuously energized, but all contacts on mechanism It would be open and a stop indication would be displayed.

It will be seen that while our invention embodies the use of timing means, the actual selection between code is accomplished by counting the number of impulses in each group and that wide variations in the various time intervals may be tolerated Without interference with the proper operation of the apparatus.

It. should also be pointed out that since the relay 9 is in each case energized in series with one of the relays 10, 11 or 12, it is plain that unless a high, medium or low speed indication is actually being displayed, the relay 9 will be (lo-energized, and the stop lamp S will be lighted.

Although we have herein shown and described only two forms of apparatus enabodying our invention, it is understood that Inn Ill)

various changes and modifications may be made therein within the scope of the a pended claims without departing from t e spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. Railway traffic controlling apparatus comprising means in the trackway for supplying code impulse combinations to a train, each combination comprising a different number of impulses, and train-carried governing means selectively responsive to the number of impulses in each combination.

2. Railway tratlic controlling apparatus comprising means in the trackway for supplying code impulse combinations to a train, means controlled by traflic conditions for varying the number of impulses in each combination, and train-carried governing mechanism selectively responsive to the number of impulses in said combinations.

3. Railway tratlio controlling apparatus comprising a stretch of railway track, means for supplying code impulse combinations to the track rails, each combination comprising a different number of impulses, and train-carried governing means controlled by energy received from the trackway and selectively responsive to the number of impulses in said combinations.

4. Railway tratfic controlling apparatus comprising a devise biased to an initial position, a relay, means efieetive when said relay is energized to. move said device a predetermined distance away from said initial position,'means effective for a fixed interval of time after said relay is de-energized for holding said device against such ins, and means for supplying said relay with code impulse combinations, the number of impulses in each combination depending upon trafiic conditions.

5. Railway traific controlling apparatus comprising a device biased to an initial position, a relay, means efiective when said relay is energized to move said device a predetermined distance away from said initial position, means effective for a fixed interval of time after said relay is de-energized for holding said device against such bias, means for supplying said relay with code impulse combinations, the number of impulses in each combination depending upon trafiic conditions, and the time interval between successive im ulses in a combination being smaller than said fixed interval of time, but the time interval between successive combinations being greater than said fixed interval'of time.

6. Railway trafiic controlling apparatus comprising a device biased to an initial position, a relay, means effective when said relay is energized to movesaid device a predetermined distance away from said initial position, means effective for a fixed interval of time after said relay is de-energized for holding said device against such bias, means for supplying said relay with code impulse combinations, the number of impulses in each combination depending upon trafiic conditions, a slow acting relay, and means for energizing said slow acting relay when said device is moved out of its initial position.

7. Railway trafiic controlling apparatus comprising a device biased to an initial position, a relay, means eifective when said relay is energized to move said device a predetermined distance away from said initial position, means effective for a fixed interval of time after said relay is de-energized for holding said device against such bias, means for supplying said relay with code impulse combinations, the number of impulses in each combination depending upon traflic conditions, a slow acting relay, means for energizing said slow acting relay when said device is moved out of its initial position, and governing means on the train controlled by said slow acting relay.

8. Railway traffic controlling apparatus comprising a train-carried relay, means for supplying said relay with code impulse combinations, means for varying the number of impulses in each combination in accordance with traflic conditions, and governing means controlled by said relay and selectively responsive to the number of impulses in each said combination.

9. Railway traffic controlling apparatus comprising a train-carried relay, means for supplying the relay with code impulse combinations, a device biased to an initial position, means'for moving said .device away from such position a predetermined amount for each energization of said relay, and governing means on the train controlled in accordance with the position of said device.

10. Railway traific contwlling apparatus comprising a train-carried relay, means for supplying the relay with code impulse coinbinations, a device biased to an initial position, means for moving said device away from such position a predetermined amount for each energization of said relay, means effective during the time interval between successive impulses in a combination to latch up said device, and governing means controlled in accordance, with the position of said device.

11. Railwaytrafiic controlling apparatus comprising a train-carried relay, means for supplying the relay with code impulse coinbinations, a device biased to an initial position, means for moving said device away from such position a predetermined amount for each energization of said relay, means effective during the time interval between successive impulses in a combination to latch up said device, a slow acting relay controlled in accordance with the position of said device and having a time period greater than aeeaaeo the time interval between successive combinations, and governing means controlled by said slow acting relay.

12. Railway trafiic controlling apparatus comprising a train-carried device biased to an initial position, means for supplying the trackway with code impulse combinations, means for varying the number otimpulses in each combination in accordance with tratiic conditions, a driving pawl on the train ar- '-anged to move said device a predetermined distance away from its initial position for each impulse and a latching pawl tor latching said device during the time interval between impulses in a combination butnot during the time interval between successive combinations.

13. Railway traflic controlling apparatus comprising meztns for supplying the track- Way with code impulse combinations, means for varying the number of impulses in each combination in accordance with traflic conditions, a plurality of contacts on the train, means for selectively operating said contacts in accordance with the number of impulses in each combination being supplied to the trackway, and governing means controlled by said contacts.

14. Railway trailie controlling apparatus comprising means for supplying the trackway with code impulse combinations, means for varying the number of impulses in each (Oll'll'llllllIlOTl in accordance with trafiic conditions. a plurality of contacts on the train, means for selectively operating said contacts in accordance with the number of impulses in each combination being supplied to the trackway, and a plurality of governing means one controlled by each of said contacts.

15. Railway traffic controlling apparatus comprising means for supplying the tracle way with code impulse combinations, means for varying the number of impulses in each combination in accordance with trallic conditions, a plurality of contacts on the train, means for selectively operating said contacts in accordance with the number of impulses in each combination being supplied to the trackway, a plurality of relays one controlled by each said contact, and governing means controlled by said relays.

16. Railway tratlic controlling apparatus comprising a train-carried device biased to aninitial position,.means for supplying the traclgway with code impulsecombinations,

means for varying the number of impulses in each combination in accordance with traffie conditions, a driving pawl on the train arranged to move said device a predetermined distance away from its initial position for each impulse supplied to the tracltway, a latching pawl for latching said device during the time interval between impulses in a combination but not during the time interval between successive combinations. and governing means controlled by said device.

17. Railway tratiic controlling apparatus comprising a train-carried device biased to an initial position, means for supplying the trackway with code impulse combinations, means for varying the number of impulses in much combination in accordance with trallic conditions, a driving pawl 0n the train arranged to move said device a predetcrn'iined distance away from its initial position for each impulse supplied to the trackway, a latching pawl for latching said device during the time interval between impulses in a combination but not during the time interval between successive combinations, and governing means controlled by said device and by said holding pawl. v

18. Railway trafiic controlling apparatus comprising means for supplying the trackw ay with code impulse combinations, a de- -.\'1ce on a train biased to an initial position.

a relay on the train arranged to be energized by each said impulse, driving mechanism ettective when said relay is energized to advance said device a predetermined distance away from such initial position, latching mechanism ell'ective after energization of said relay for a time interval greater than the. interval between impulses in the same combination to prevent the return of said device to its initial position, a plurality of contacts arranged to be successively closed as said device is moved away from its initial position, and governing means controlled by said contacts and including slow acting means having a time interval greater than the time interval between successive combinations.

19. Railway traliic controlling apparatus comprising means for supplying the trackway with code impulse combinations, a device on a train biased to an initial position. a relay on the train arranged to be energized by each said impulse, driving mechahism cll'ective when said relay is energized to advance said device a predetermined distance away from such initial position, latching mechanism ettective after energization of said relay for a time interval greater than the interval between impulses in the same combination to prevent the return of said device to its initial position, a plurality of contacts arranged to be successively closed as said device is moved away from its initial position, and governing means controlled by said contacts and by said latching mechanism.

20. Railway traiiie controlling apparatus comprising means for supplying the traclc way with code impulse combinations, a device one train biased to an initial position. a train-carried relay adapted to be energized by each said impulse, means effective after energization of said relay for a time interval said bias, an escapement for releasing said device for limited movement by said force when said relay is energized, and govermng means responsive to the position 01' said de- ,vice.

21. Railway trafiic controlling apparatus comprising means for supplying the trackway with code impulse combinations, means for varying the number of impulses in each combination in accordance with traffic conditions, a device biased to an initial pos1 tion, a train-carried relay arranged to be energized by each said impulse, means for applying to said device each time said relay is energized a force tending to move the device against said bias, an escapement normally preventing movement of said device by said force, means for actuating said escapement when said relay is energized to allow movement of the device for a predetermined distance, the device being arranged to return to its initial position during the time interval between successive combinations, a contact arranged to be closed as the device returns to its initial position, and governing means controlled by said contact.

22. Railway trailic controlling apparatus comprising a train-carried relay, means for supplying the relay with code impulse combinations, a device biased to an initial position, means for moving said device away from such position a predetermined amount for each energization of said relay, a contact ar 'anged to be closed when said device is returning to said initial position, a'slow acting relay controlled by said contact, and governing means controlled by said slow acting relay.

.23. Railway tratlic controlling apparatus comprising a train-carried relay, means for supplying the relay with code impulse combinations, a device biased to an initial position, means for moving said'device away from such position a predetermined amount for each energization of said relay, a plurality of controlling contacts selectively operated depending upon the position of said device, a bridging contact arranged to be closed when said device is returning to said initial position, a plurality of slow acting relays each controlled by an associated one of said controlling contacts all said relays being controlled by said bridging contact, and governing means controlled by said slow acting relays.

24. Railway trafiic controlling apparatus comprising a train-carried relay, means for supplying the relay with code impulse combinations, a device biased to an initial position, means for moving said device away from such position a predetermined amount for each energization of said relay, a first contact controlled by the position of said device, a second contact arranged to be closed only when said device is returning to said initial position, a slow acting relay controlled by said two contacts, and governing means controlled by said slow acting relay.

25. Railway traflic controlling appa'atus comprising a traincarried relay, means for supplying the relay with code impulse combinations, a device biased to an initial position, means for moving said device away from such position a predetermined amount for each energization of said relay, means eli'ective during the time interval between successive impulses in a combination to latch up said device, a contact arranged to be closed for a brief interval after such latching means becomes ineffective, a slow acting relay controlled by said contact, and governing means controlled by said slow acting means.

26. In a continuous indication train control system, in combination, a translating device on the train, means controlled by traflic conditions for transmitting electrical impulses through said translating device, stepby-step mechanism controlled by said translating device operating through a certain number of steps and then returning to initial position continually so long as impulses are transmitted through said translatin device, and indication means controlled lay said mechanism and held at. one indication only so long as said mechanism completes its phase of operation in predetermined intervals.

27. In a continuous indication train control system, in combination, a track, :1 vehicle travelling thereon, a translating device on the vehicle, means controlled by trafiic conditions for transmitting electrical impulses through said translating device, a member on the vehicle moved to an initial position upon the reception of each impulse, constantly acting means for moving said member away from initial position at a predetermined rate, a train control magnet, and means for closing a circuit therethrou gh upon the reception of each impulse. only if said member has reached a certain position.

In testimony whereof we ailix our signatures.

LARS O. GRONDAHL. LEWIS L. NETTLETON. 

